1. Field of the Invention
The present invention relates to an antenna, and in particular to a tri-band antenna employed in a mobile electronic device.
2. Description of the Prior Art
U.S. Pat. No. 6,552,685, discloses a flat antenna comprising radiation elements, a first dielectric substrate and a back ground plate. The radiation elements are constituted of a conductive plate provided on the front face of the first dielectric substrate and the back ground plate is constituted of a conductive plate provided on the rear face of the first dielectric substrate. However, the radiation elements, the first dielectric substrate and the back ground plate are integrated to overlap each other and mounted into a mobile electronic device. When the mobile electronic device is vibrated or swayed, friction will be generated between the antenna and the mobile electronic device, which result in that the antenna is damaged and signals transmitted by the antenna is not steadily.
Hence, an improved antenna is desired to overcome the above-mentioned shortcomings of the existing antennas.